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51.
52.
Irin Parvin Abu Sadat Mohammad Sayeem Bin Shahid Subhasish Das Lubaba Shahrin Mst. Mahmuda Ackhter Tahmina Alam Soroar Hossain Khan Mohammod Jobayer Chisti John D. Clemens Tahmeed Ahmed David A. Sack Abu Syed Golam Faruque 《PLoS neglected tropical diseases》2021,15(9)
BackgroundAfter a multi-country Asian outbreak of cholera due to Vibrio cholerae serogroup O139 which started in 1992, it is rarely detected from any country in Asia and has not been detected from patients in Africa.Methodology/Principal findingsWe extracted surveillance data from the Dhaka and Matlab Hospitals of International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) to review trends in isolation of Vibrio cholerae O139 in Bangladesh. Data from the Dhaka Hospital is a 2% sample of > 100,000 diarrhoeal patients treated annually. Data from the Matlab Hospital includes all diarrhoeal patients who hail from the villages included in the Matlab Health and Demographic Surveillance System. Vibrio cholerae O139 was first isolated in Dhaka in 1993 and had been isolated every year since then except for a gap between 2005 and 2008. An average of thirteen isolates was detected annually from the Dhaka Hospital during the last ten years, yielding an estimated 650 cases annually at this hospital. During the last ten years, cases due to serogroup O139 represented 0.47% of all cholera cases; the others being due to serogroup O1. No cases with serogroup O139 were identified at Matlab since 2006. Clinical signs and symptoms of cholera due to serogroup O139 were similar to cases due to serogroup O1 though more of the O139 cases were not dehydrated. Most isolates of O139 remained sensitive to tetracycline, ciprofloxacin, and azithromycin, but they became resistant to erythromycin starting in 2009.Conclusions/SignificanceCholera due to Vibrio cholerae serogroup O139 continues to cause typical cholera in Dhaka, Bangladesh. 相似文献
53.
Isolation of novel bacteria, including a candidate division, from geothermal soils in New Zealand 总被引:4,自引:0,他引:4
Stott MB Crowe MA Mountain BW Smirnova AV Hou S Alam M Dunfield PF 《Environmental microbiology》2008,10(8):2030-2041
We examined bacterial diversity of three geothermal soils in the Taupo Volcanic Zone of New Zealand. Phylogenetic analysis of 16S rRNA genes recovered directly from soils indicated that the bacterial communities differed in composition and richness, and were dominated by previously uncultured species of the phyla Actinobacteria , Acidobacteria , Chloroflexi , Proteobacteria and candidate division OP10. Aerobic, thermophilic, organotrophic bacteria were isolated using cultivation protocols that involved extended incubation times, low-pH media and gellan as a replacement gelling agent to agar. Isolates represented previously uncultured species, genera, classes, and even a new phylum of bacteria. They included members of the commonly cultivated phyla Proteobacteria , Firmicutes , Thermus/Deinococcus , Actinobacteria and Bacteroidetes , as well as more-difficult-to-cultivate groups. Isolates possessing < 85% 16S rRNA gene sequence identity to any cultivated species were obtained from the phyla Acidobacteria , Chloroflexi and the previously uncultured candidate division OP10. Several isolates were prevalent in 16S rRNA gene clone libraries constructed directly from the soils. A key factor facilitating isolation was the use of gellan-solidified plates, where the gellan itself served as an energy source for certain bacteria. The results indicate that geothermal soils are a rich potential source of novel bacteria, and that relatively simple cultivation techniques are practical for isolating bacteria from these habitats. 相似文献
54.
Finding and comparing syntenic regions among Arabidopsis and the outgroups papaya, poplar, and grape: CoGe with rosids 总被引:1,自引:0,他引:1
Lyons E Pedersen B Kane J Alam M Ming R Tang H Wang X Bowers J Paterson A Lisch D Freeling M 《Plant physiology》2008,148(4):1772-1781
In addition to the genomes of Arabidopsis (Arabidopsis thaliana) and poplar (Populus trichocarpa), two near-complete rosid genome sequences, grape (Vitis vinifera) and papaya (Carica papaya), have been recently released. The phylogenetic relationship among these four genomes and the placement of their three independent, fractionated tetraploidies sum to a powerful comparative genomic system. CoGe, a platform of multiple whole or near-complete genome sequences, provides an integrative Web-based system to find and align syntenic chromosomal regions and visualize the output in an intuitive and interactive manner. CoGe has been customized to specifically support comparisons among the rosids. Crucial facts and definitions are presented to clearly describe the sorts of biological questions that might be answered in part using CoGe, including patterns of DNA conservation, accuracy of annotation, transposability of individual genes, subfunctionalization and/or fractionation of syntenic gene sets, and conserved noncoding sequence content. This précis of an online tutorial, CoGe with Rosids (http://tinyurl.com/4a23pk), presents sample results graphically. 相似文献
55.
对普通小麦(Ttiticum aestivum)黄色素(YP)合成途径中的首要限速酶——八氢番茄红素合成酶(Psy)基因进行克隆和测序,并和玉米Psy基因进行序列比对。结果表明,在高和低YP含量小麦品种中均扩增出一条长1192bp的Psy基因片段,该片段包含一条可编码78个氨基酸的小麦Psy基因的外显子,与玉米Psy基因第4外显子的核苷酸序列同源率为80.74,同源区域内有47个SNPs,但仅11个SNPs导致氨基酸编码序列的改变,二者氨基酸序列的同源率达85.89,推测Psy基因在不同物种中的表达具有较高的保守性。BLAST聚类分析表明,禾谷类植物Psy基因的分类与物种的亲缘关系存在明显的相关性,小麦Psy基因在系统进化中比禾谷类其他植物更为高级。 相似文献
56.
Robert E. Paull Beth Irikura Pingfang Wu Helen Turano Nancy Jung Chen Andrea Blas John K. Fellman Andrea R. Gschwend Ching Man Wai Qingyi Yu Gernot Presting Maqsudul Alam Ray Ming 《Tropical plant biology》2008,1(3-4):246-277
Papaya (Carica papaya L.) is the first fleshy fruit with a climacteric ripening pattern to be sequenced. As a member of the Rosids superorder in the order Brassicales, papaya apparently lacks the genome duplication that occurred twice in Arabidopsis. The predicted papaya genes that are homologous to those potentially involved in fruit growth, development, and ripening were investigated. Genes homologous to those involved in tomato fruit size and shape were found. Fewer predicted papaya expansin genes were found and no Expansin Like-B genes were predicted. Compared to Arabidopsis and tomato, fewer genes that may impact sugar accumulation in papaya, ethylene synthesis and response, respiration, chlorophyll degradation and carotenoid synthesis were predicted. Similar or fewer genes were found in papaya for the enzymes leading to volatile production than so far determined for tomato. The presence of fewer papaya genes in most fruit development and ripening categories suggests less subfunctionalization of gene action. The lack of whole genome duplication and reductions in most gene families and biosynthetic pathways make papaya a valuable and unique tool to study the evolution of fruit ripening and the complex regulatory networks active in fruit ripening. 相似文献
57.
S. T. Chandel H. S. Gaur M. M. Alam 《Archives Of Phytopathology And Plant Protection》2013,46(4):287-290
Abstract Horsfall, J. G. (Ed.): Annual Review of Phytopathology. Vol. 4. VII + 423 S. Palo Alto, 1966: Annual Reviews, Inc. Leinen, 9,00 $. Reviewed by K. Naumann. Gregory, P. H. und Monteith, J. L. (Ed.): Airborne microbes. Seventeenth Symposium of the Society for General Microbiology held at the Imperial College, London April 1967. XII + 385 S., mit Abb. u. Tab. London, 1967: Cambridge University Press, Leinenrücken, 75 s. Reviewed by H. J. Müller. Raper, J. R.: Genetics of sexuality in higher fungi. VIII + 283 S., mit Abb. u. Tab., New York, 1966: The Ronald Press Company, Leinen, 12,00 $. Reviewed by M. Schmiedeknecht. Albrecht, F. O.: Polymorphisme phasaire et biologie des acridiens migrateurs. X + 194 S., 52 Abb. Paris, 1967: Masson et Cie, Éditeurs, karton., 50 F. Reviewed by R. Fritzsche. Wigglesworth, V. B.: Insect physiology. VII + 134 S., 12 Abb., London, 1966: Methuen &; Co Ltd., brosch., 10 s 6 d. Reviewed by G. Schäller. Machlis, L. (Ed.): Annual Review of Plant Physiology. Vol. 18. VIII + 480 S., mit Abb. u. Tab., Palo Alto, Ca., 1967: Annual Reviews, Inc., Leinen, 9,00 $. Reviewed by H. Wolffgang. Newton, B. A. und Reynolds, P. E. (Ed.): Biochemical studie of antimicrobial drugs. (Sixteenth symposium of the Society for General Microbiology held at the Royal Institution, London, April 1966). X + 349 S., mit Abb. u. Tab., London, 1966: Cambridge University Press, Halbleinen, 60 s. Reviewed by H. J. Müller. Pilet, P.-É.: La cellule, structure et fonctions. 406 S., 310 Abb.; 32 ganzs. Abb., Paris 1966: Schwarz-Weiß-Tafeln. Masson et Cie, Editeurs, brosch. 38 F. Reviewed by K. Schmelzer. Ciba (Ed.): Dimecron 257 S. Basle, Switzerland, 1967: P.O. Box — CIBA — Kunststoff Reviewed by Horst Beitz. Bellamy, L. J.: Ultrarot-Spektrum und chemische Konstitution. 2. Auflage, 325 S., 11 Abb., 23 Tab. Darmstadt, 1966: Dr. Dietrich Steinkopff Verlag, kart., 28,— DM Reviewed by Volker Müller. Bahr, G. F.; Zeitler, E. H. (Ed.): Quantitative electron microscopy. 1965, VIII + 605 (1340) S., mit Abb. u. Tab., Leinen, 16,00 $, Baltimore (Md.), The Williams &; Wilkins Company. Reviewed by H. B. Schmidt. 相似文献
58.
强光照和全黑暗条件下荒漠沙蜥视网膜内GAP-43表达的免疫组织化学 总被引:2,自引:0,他引:2
采用免疫组织化学技术研究了在强光照和全黑暗条件下荒漠沙蜥(Phrynocephalus prezewalskic)视网膜内生长相关蛋白GAP-43的表达变化。结果表明,在正常光照条件下,视网膜内GAP-43阳性表达部位主要存在于内网层;强光照条件下,GAP-43免疫染色部位主要出现在内网层、节细胞层和内核层的部分细胞核。在全黑暗条件下,在视纤维层和内网层呈阳性染色;提示视网膜在不同环境条件下GAP-43的不同定位,可能与其在相应的环境下参与不同的视觉功能有关。 相似文献
59.
Epsilon toxin (ETX) is an extremely potent pore‐forming toxin and a category B biological agent. ETX is a major virulence determinant of Clostridium perfringens toxinotypes B and D, and is implicated in pathogenesis of rapidly fatal economically important pulpy kidney disease in lambs caused by toxinotype D. Despite being a toxin, ETX can be utilized as a tool to target glutamatergic neurons and for drug delivery into the CNS. 2DE‐MS approach was employed to elucidate the host response to ETX following intravenous injection in mouse model. In total, 136 proteins were identified either differentially expressed in brain (18) and kidney (33); showing specific interaction with ETX from lysates of brain (4), kidney (21), or from plasma (42); and urine markers (18) of intoxication. Differentially expressed proteins in kidney included those involved in calcium homeostasis and cytoskeletal organization. Proteins involved in ER and oxidative stress and energy metabolism also showed differential levels in the target tissue after ETX treatment. The known functions of the proteins differentially expressed and those interacting with ETX indicate involvement of interlinked pathways. This study provides first proteomic account of host response to ETX exposure providing clues to mechanism of toxicity and potential therapeutic targets. 相似文献